As an engineer I also queried this with our tech services guys as I was of the opinion that Land 2 is Cat 3a.
The reply I got was that for a particular failure scenario, although the a/c was then fail passive a subsequent
similar failure would result in
possible a/c configuration problems after a disconnect. This, coupled with the fact that our ASA is set up to display only on multi channel eng, meant that there was not enough time to carry out the drill to establish if the landing could continue as Cat3 or had to be downgraded to Cat2.
Hence for our ops Land 2 = Cat 2
looking into the system there is only one area where there are not 3 channels and that is the stab. I am not familiar with crew drills for Cat3 landings but I suggest it is possible that companies with a different SOP/pre-landing drill have in their proceedures a (probably quite simple) check that is done to ensure correct stab failure backup.
However I am prepared to back down on this as I was not very happy with the quality of the response from the tech services chap, in fact my initial response was
if I recall.
